Albright et al., U.S. Pat. No. 4,083,825 (1978) and Stanaback et al., U.S. Pat. No. 4,046,719 1977) illustrate certain halogen-substituted phosphates useful as flame retardants in polyurethanes. The phosphates of Stanaback et al. can be certain bis(phenyl) halogenated phosphates.
A problem in the art is production of highly marketable polyurethanes, particularly flexible foams and especially as slabstock. Therein, scorch, odor, processability and flame-retardant efficiency are among production characteristics often needing improvement.